case 1):
284 good fish, 23 bad fish (no surprise, I did not finish that quest), could conclude to a roughly 7.5% chance fishing something unwanted
the probability finishing 50 casts in a row is about 2%.
Since not many characters have finished this quest, this seems quite high

All of the above value are my own records, some tries were not recorded. If there is a trick, completing this quest, I would like to know it, since I wasted much time on it
The fishing skill seems to have no effect on this quest, I have 200 fishing and failed on cast #4, and fishing 30 and got 25.

All in all this quest is very time consuming and frustrating. I would like to know, how many characters completed this quest worldwide.

I think the probability also relies on placement. Last year I noticed that few spots have drastically higher probability to get a good catch. Hint: I am usually the only one standing in those spots. Everyone else is no where's close to where I stand.

Why am I not giving away these locations? Just like in irl fishing, if everyone fishes there, the probability of catching what you want decreases.

Don't follow the crowd, find a spot where no one is and go for it.

P.S. My two tries this year (baby to blame for low number) were 46/50 and 38/50 towards completion. Will be giving it another try soon.

I will update my statistic after the end of the farmer's faire.
Honestly, I think Turbine should change that quest, either lowering the fail-chance, or introduce steps, so you don't have to restart from scratch, lower the chances, if you fished enough fishes, allow to fish more than one bad fish, etc. Something should be done so that quest is finishable, which is in my opinion virtually impossible.

So I advice anyone not to start this quest, it is very annoying.
In total I fished 1801 objects, which approximating each catch to 10 seconds is 18010 seconds, i.e. ~300 minutes or 5 hours completely wasted. My best try was 34 good fishes.
This quest should be improved, either by:
- removing the fail cooldown (which will not make the quest possible)
- chance the probability

>assumed probabilities of 5/10/15/25/50% would result in an overall probability succeeding this quest of 0.00022602843691258993 %
>even if they are 5/10/15/20/25% the overall chance is: 0.02485208945934268% (sums up to 0.2969488492851967% for 14 tries you have over the whole faire)
>changing the probalities to 1/2/3/4/5% would result in a 21.69094278748693% chance succeeding this quest

- introduce steps, so if you made 10 fishes, you never have to catch them again (would prevent fish-farming
- allow to fish more bad fish (which could be against the intention of this quest)

Your hypothesis has merit. If you wish to test it, I suggest sharing your spot with a few trustworthy people on other servers and getting a lot more data. In my own experience, location has little or no affect on results.

May I ask, why should I use numbers different from those I acquired from observation?
They may vary with each try, but they are around 5%,10%,20%,30%,??% failing (last step I have no data)
My excact numbers will follow when the festival is over, and I will bug it (a quest which cannot be accomplished, is a bug IMHO)

The chance is a bit better, but ridiculously low. Being struck by lightning seem to have better odds.

I even tried different positions, used the horseshoe, made no difference (since I just did about 10 fishing sessions per day, we should not rely on it)
I did many session at the same spot (the fishing net near the quest-giver) and I got the bad fish somewhere between fish#1 and #34 (even on the first try)

Possible improvements for this quest could be:
- use an internal counter to decrease the odds for the bad fish (e.g. odds for the easy fish are: 5%-0.1%per easy fish caught in previous runs), so doing this quest would increase your odds to finish it.
- could the fish in the inventory/bag and credit them (e.g. if I have 10 easy fish in inventory/bag, I start with the Tier 2-fish)

So I advice anyone not to start this quest, it is very annoying.
In total I fished 3238 objects, which approximating each catch to 30 seconds is 971400 seconds, i.e. ~1619 minutes or ~27 hours completely wasted. My best try was 34 good fishes.
This quest should be improved, either by:
- removing the fail cooldown (which will not make the quest possible)
- chance the probability

>assumed probabilities of 5/10/15/25/50% would result in an overall probability succeeding this quest of 0.00022602843691258993 %
>even if they are 5/10/15/20/25% the overall chance is: 0.02485208945934268% (sums up to 0.2969488492851967% for 14 tries you have over the whole faire)
>changing the probalities to 1/2/3/4/5% would result in a 21.69094278748693% chance succeeding this quest
>use an internal counter to decrease the odds for the bad fish (e.g. odds for the easy fish are: 5%-0.1%per easy fish caught in previous runs), so doing this quest would increase your odds to finish it.

starting probability for all tiers are set to 50%
every good catch of a fish reduces the probability for the bad fish by 3/2/1/1/1 %
so if you do the quest and do your first cast, the probability for the bad fish is 50%.
the first success reduces the bad fish probability to 47%, after 17 successful easy fishes (which cannot be accomplished in one session, even if you are lucky) you will have no chance to fail on easy fishes.
I hope you get the idea. (You could use 50-(fishes of the appropriate tier in inventory) as probability, just an idea)

> credit the fish in the inventory/bag (e.g. if I have 10 easy fish in inventory/bag, I start with the Tier 2-fish)

- introduce steps, so if you made 10 fishes, you never have to catch them again (would prevent fish-farming
- allow to fish more bad fish (which could be against the intention of this quest)[/QUOTE]

even if I personally like the idea of an internal counter, I could understand that it would need to some additional work, changing the overall probability seems the easiest way to improve this quest.
As said: 1/2/3/4/5% fail chance would chance the probabilty to about 20% which seems fair, something around the calculated 0.0002% is right frustrating

PS: this assumes, there is no secret trick to identify the bad fish of manipulate the probability
PPS: I would like to know if there is someone, who managed to catch all 50 fishes

By now it should be obvious to everybody that the chances of actually completing this quest are extremely small at best.

BUT keep in mind that all the fishes caught can be bartered for Farmer's Faire Tokens (which can in turn be bartered for various stuff.)
Therefore I think that it is a mistake to think of it as a quest that cannot realistically be completed (even though it is exactly that).
It is better to think of it as just an extra way of obtaining tokens - one that you might even get a title from if you are extremely lucky.

Another frustrating farmers faire past and here the numbers for this year:

Tier of the fish

# of fishes in the current streak (apparently none, since the quest is not active any more)

# of good fishes in total this year for this tier

# of bad fishes in total this year while trying this tier

probability to catch the bad fish during current tier (basically #4 divided by (#3+#4))

probability to survive current tier, based on #5

# of good fishes in total over all years for this tier

# of bad fishes in total over all years while trying this tier

probability to catch the bad fish during current tier (basically #8 divided by (#7+#8))

probability to survive current tier, based on #9

# of good fishes in total up to current year (current excluded) for this tier

# of bad fishes in total up to current year (current excluded) while trying this tier

probability to catch the bad fish during current tier (basically #12 divided by (#11+#12))

probability to survive current tier, based on #13

As you can see, I tried this quest quite some time and I never got near the end. The number seem to be o.k. since I never got to tier 5 (which is according to tool-tip a 50% chance in each catch to fail (which would be successful in 1 out of 1024 cases))

So, Turbine, please change this!
I suggest additional 5 deeds, one for each tier, which reduce the fail chance to nearly 0% when completed. Each deed will require 50 fishes of the tier to complete. So after fishing 50 easy fish, you will never fail on tier 1.
That would make that quest completeable, but a lot of work.

Another frustrating farmers faire past and here the numbers for this year:

2015:
2016:

Tier of the fish

# of fishes in the current streak (apparently none, since the quest is not active any more)

# of good fishes in total this year for this tier

# of bad fishes in total this year while trying this tier

probability to catch the bad fish during current tier (basically #4 divided by (#3+#4))

probability to survive current tier, based on #5

# of good fishes in total over all years for this tier

# of bad fishes in total over all years while trying this tier

probability to catch the bad fish during current tier (basically #8 divided by (#7+#8))

probability to survive current tier, based on #9

# of good fishes in total up to current year (current excluded) for this tier

# of bad fishes in total up to current year (current excluded) while trying this tier

probability to catch the bad fish during current tier (basically #12 divided by (#11+#12))

probability to survive current tier, based on #13

As you can see, I tried this quest quite some time and I never got near the end. The number seem to be o.k. since I never got to tier 5 (which is according to tool-tip a 50% chance in each catch to fail (which would be successful in 1 out of 1024 cases))
I also changed some of my output just concerning the number of digits for the numbers.

So, Turbine, please change this!
I suggest additional 5 deeds, one for each tier, which reduce the fail chance to nearly 0% when completed. Each deed will require 50 fishes of the tier to complete. So after fishing 50 easy fish, you will never fail on tier 1.
That would make that quest completeable, but a lot of work.